CHICAGO — The gold coins have arrived in much the same manner every year for the past four years: An anonymous donor dropped each one into a Salvation Army kettle somewhere in Fort Myers, Fla.

Each coin was tucked inside a small plastic case with a neatly handwritten note that said simply, "In memory of Mimi."

Every holiday season, such acts of generosity raise intriguing questions about the mysterious unknown donors. These "secret Santas" provide gifts ranging from plates of cookies to substantial piles of cash, and they are not in it for the glory or even the tax write-off. Many go to great lengths to keep their identities cloaked.

"It's a little magical, isn't it?" says Mary Davidson, who oversees a small group of anonymous donors known publicly only as the "Dream Team" at the Society of Memorial Sloan-Kettering Cancer Center in New York City. The group grants wishes to adults who are seriously ill, much like the Make-A-Wish Foundation does for children.

Each Christmas, they also secretly send holiday gifts and dinner with all the trimmings to a needy patient and family.

Last year, a convenience store manager outside Little Rock, Ark., bought clothing, toys and a few small Christmas gifts for a struggling family.

The mother of the family, whose husband had lost his job, could not believe the unsolicited generosity.

'Goodness again'
"I'd felt a little pessimistic. I'm down on a lot of people when I know I shouldn't be," she says. "But then she did that, and I could see goodness again."

She asked not to be identified, partly because she does not want the woman who provided the gifts to know that she figured out her identity.

There is, after all, a tacit understanding among secret Santas that privacy will be respected.

At the National Philanthropic Trust in suburban Philadelphia, donors are careful to conceal anything that might reveal them.

One client distributes donations using only the name "Santa's Silent Elves." Another asks that donation checks be coded only with numbers and mailed from a random location.

Others use several trust organizations to deliver smaller checks so recipients do not know that the entire donation came from the same person or family.

"I think of it as a higher form of philanthropy," says Eileen Heisman, president and CEO of the trust. She's worked at other organizations where donors making public gifts have asked "How big are the letters going to be on the plaque?" that recognizes their contribution.

Anonymous $30,000 gift
She and her staff still remember the donor who sent an anonymous $30,000 grant to a school in Louisiana. The school then gave the money to a custodian who had also been a coach so he could get a college degree. In that case, the donor did not want to embarrass the custodian or make him feel obligated in any way.

Other secret donors say they do not want to flaunt their wealth, especially when so many are struggling in a weak economy.

That's the case for a 59-year-old investment banker in New York City whose favorite charities include DonorsChoose.org, a Web site that seeks donations for educational causes.

She likes the fact that teachers can post their classroom needs on the site. Then donors can select a project to support — and do so anonymously.

"The idea is we're all in it together," she says. She often waits until a posting is about to expire and then steps in and donates the remaining cash.

This year, she gave about $20,000 to DonorsChoose causes, roughly a fifth of her overall annual giving. Among other things, she paid for chairs for a classroom that did not have enough, and for ping-pong and pool tables for teachers who wanted to use the games to help students learn physics.

Year-round secret Santa
For her, being a secret Santa is a year-round endeavor.

"When I'm really feeling stressed-out ... and generally unhappy, I go to DonorsChoose and I look for something I want to make happen," she says. "It's incredibly rewarding. And that's enough of a return."

There are other reasons for remaining anonymous, too, some of which might not be so altruistic.

Some people do not want others to know how little they are giving, either because they cannot give more or because they do not want to.

Other donors, especially those who are wealthy, do not want to be repeatedly approached for more money.

"Once you become known, people come out of the woodwork," says Ron Hill, a marketing and management professor at the Villanova University School of Business. He works on fundraising strategies with nonprofit organizations and has studied the various types of donors, including secret Santas.

"For them," he says, "the gift is only between them and their maker, and maybe a few close friends or a spouse."

Who is Mimi?
In Fort Myers, the Salvation Army cannot help but wonder about the donor who gave the gold coins, including this year's donation, a 1908 St. Gaudens Double Eagle coin valued at about $1,000.

Is he or she an elderly coin collector or someone younger? And who is Mimi — a long lost love or friend?

Megan Spears, resource management director for the Fort Myers Salvation Army, has studied the handwriting on the notes that arrive with the coins. She is quite certain they were written by the same person.

She is grateful for the gifts and the attention they bring, particularly when donations are down. And she's happy to leave it at that.

"The mystery," she says, "is part of the excitement."

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